Pointers in C++

A pointer is an integer, which stores a memory address. Types can be used with pointers but more on a syntactical-level to make clear what the value retrieved will be. Under the hood, using types for a pointer doesn’t change anything at all.

// surely the simplest pointer one could write.
void* ptr = nullptr;

int var = 8;
// assining the memory address of this value to the pointer:
void* ptr = &var;

// would lead to the same result:
int* ptr = &var;

Only when assining for example an double to this pointer as type, this would lead to an error.

Writing to the data behind the memory address:

int var = 8;
int* ptr = &var;
*ptr = 10;

Creating a variable on the heap

// asks for 8 bytes of memory, returns a pointer
char* buffer = new char[8];
// 8 bytes, all set to 0. This is heap-allocated
memset(buffer, 0, 8);
// therefore needs to be deleted:
delete[] buffer;